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Potential targets of Plasmodium ookinetes at the mosquito midgut walls were investigated in relation to interfering malarial transmission. In this study, the essential application of Quantum Dots (QDs) was used to examine the interaction between Plasmodium berghei ookinetes and the Anopheles stephensi midgut, based on lectin-carbohydrate recognition. Two significant lectins were utilized to determine this interaction. Two QDs, cadmium telluride (CdTe)/CdS and cadmium selenide (CdSe)/CdS, were employed in staining Plasmodium ookinete to study its interaction in the midgut of the mosquito vector in vivo. Concurrently, two lectins, wheat germ agglutinin (WGA) and concanavalin A (Con A), were inadvertently exploited to mask lectin binding sites between ookinetes and mosquito midgut cells. The numbers of ookinetes in both lumen and epithelial cells were eventually counted, following adequate preparation of wax sections extracted from whole midgut, and subsequent examination using a differential interference contrast a fluorescence microscopic technique. Interestingly, we detected that neither of the QDs mutated ookinete invasion into the midgut cells of the investigated mosquitoes. QD staining of ookinetes remained permanent despite the effective embedding procedure. The massive binding potency of ookinetes to midgut cells of the cross-examined mosquitoes undoubtedly revealed that Con A did not interrupt ookinete penetration into the midgut wall. In contrast, WGA inhibited ookinete invasion into the midgut cells. The results proved that QD nanoparticles are biocompatible, non-toxic to P. berghei and stable to photobleaching. The QDs staining, which was successfully implemented for ookinete labelling, is a simple and effective tool which plays a crucial role in bioimaging including the study of parasite-vector interactions., (Copyright © 2016 Elsevier B.V. All rights reserved.)

This study investigated loop-mediated isothermal amplification (LAMP) detection of Plasmodium falciparum and Plasmodium vivax in urine and saliva of malaria patients. From May to November 2011, 108 febrile patients referred to health centers in Sistan and Baluchestan Province of south-eastern Iran participated in the study. Saliva, urine, and blood samples were analyzed with nested PCR and LAMP targeting the species-specific nucleotide sequence of small subunit ribosomal RNA gene (18S rRNA) of P. falciparum and P. vivax and evaluated for diagnostic accuracy by comparison to blood nested PCR assay. When nested PCR of blood is used as standard, microscopy and nested PCR of saliva and urine samples showed sensitivity of 97.2%, 89.4% and 71% and specificity of 100%, 97.3% and 100%, respectively. LAMP sensitivity of blood, saliva, and urine was 95.8%, 47% and 29%, respectively, whereas LAMP specificity of these samples was 100%. Microscopy and nested PCR of saliva and LAMP of blood were comparable to nested PCR of blood (к=0.95, 0.83, and 0.94, respectively), but agreement for nested PCR of urine was moderate (к=0.64) and poor to fair for saliva LAMP and urine LAMP (к=0.38 and 0.23, respectively). LAMP assay showed low sensitivity for detection of Plasmodium DNA in human saliva and urine compared to results with blood and to nested PCR of blood, saliva, and urine. However, considering the advantages of LAMP technology and of saliva and urine sampling, further research into the method is worthwhile. LAMP protocol and precise preparation protocols need to be defined and optimized for template DNA of saliva and urine., (Copyright © 2014 Elsevier B.V. All rights reserved.)